case report Repetitive behaviors have often been described in patients with brain lesions but may be part of obsessive-compulsive spectrum disorders.
We report a case of a 65-year-old man who presented with repetitive whistling after post anoxic frontal syndrome. We strive to differentiate between an impulse control disorder due to frontal disinhibition, repetitive behavior due to structural brain lesion and obsessive-compulsive disorder (OCD). Our patient  did not show a history of obsessive-compulsive symptoms or other psychiatric complaints prior to the hypoxic incident. The patient did not feel forced to whistle, but expressed feelings of anxiety if asked to stop. Previous treatment with clomipramine had resulted in a decrease of whistling, but also caused unacceptable complaints of incontinence. A structural mri showed cortical atrophy, most prominent in frontal and temporal areas.
method Several case studies report on patients that demonstrate similar repetitive behaviors after specific brain lesions. Further, repetitive behavior is often described in Parkinson’s patients with dopamine dysfunction (punding) and in frontotemporal dementia. We conclude that patient’s repetitive behavior cannot be explained by OCD or disinhibition with frontal syndrome. Given the clinical   resemblance between our patient’s behavior and repetitive behavior that is seen in dopamine  dysfunction syndrome with punding and frontotemporal dementia, we consider dopamine-serotonin  dysfunction as an etiologic factor.